The present invention relates to a method for coating a press roll and in particular a center roll used in the press section of a paper machine. The invention also relates to a center roll formed by the method and used in a press section of a paper machine.
At present, center rolls used in press sections of paper machines are coated with a ceramic. However, when ceramic center rolls are employed in the press section, it is difficult to control the properties of separation and/or adhesion of the paper web.
Impregnation of a ceramic coating with plastic is known in the prior art. However, this technique has been applied so that the whole face of the roll is treated, in which case pores present in the roll face are fully or partly filled with plastic. In such an embodiment, all of the surface properties of the roll are changed, and it is a significant drawback that the desired, advantageous properties of a pure non-impregnated ceramic cannot be utilized.